Heating apparatus



Patented Jan. 9, 1934 UNETED STATES PATENT OFFICE Application December 12, 1931 Serial No. 580,605

3 Claims.

My invention relates to new and useful improvements in heating apparatus and more particularly warm air furnaces or generators.

It is one of the principal objects of my invention to provide in a warm air furnace a revolving combined grate and fire bowl.

It is another important object of my invention to provide a separate air passage for each leader connection from the cold air inlet to the bonnet of the casing.

It is still another object of my invention to provide in a warm air furnace, baiile means to conduct additional heat to the fire box walls and lower the flue temperature. It is also still another object of my invention to provide in a Warm air furnace, a rotary sleeve damper within a horizontal flue above the firebox to equalize the heat distribution within the fire box.

Other important and incidental objects of my invention will be set forth in the following specification and the claims annexed thereto.

In the accompanying drawing illustrating my invention, Figure 1 is a front View of my improved warm air furnace. Figure 2 is a sectional view taken behind the front casing. Figure 3 is a longitudinal sectional view taken on the center line of the furnace. Figure 4 is a detail view of a portion of one of the circular grate bars. Figure 5 is a detail view showing the rotary grate rotating pinions. And Figure 6 is a detail view of the rotary grate supporting rollers, employed with the pinions shown in Figure 5 to support the grate.

Referring now to the drawing for a detailed description of my invention, the numeral 1 indicates a sheet metal casing of rectangular form supported upon a base ring 2. The casing 1 converges at its top to form a bonnet 3 having inclined side portions 4-4 and a central fiat portion 5. (See Figures 1 and 2.)

The casing 1 around its front end edges, is provided with a fiange 6 to which a cast iron or cast steel front '7 is attached by screws passing through the latter and the flange.

The casing l is likewise formed with a flange 8 surrounding its rear edges, to which is secured a back 9 of sheet metal. (See Figure 3.)

Extending longitudinally within the casing 1 is a rectangular firebox 10 preferably constructed of welded steel sheets and supported on a base ring 11. The sides of the firebox below the casing bonnet 3 are inwardly inclined to form a dome 12 and a narrow elongated throat 13 at its apex.

Above the throat 13 is a horizontal circular flue passage 14 that receives the throat and extends rearwardly through the back 9 of the casing. Rotatably mounted within the flue passage 14 is a cylindrical damper 15 with open ends and having in one side an axial opening 16 co-extensive with the throat 13. Secured within the damper and at right angles to the opening 16 are stiifeners 171'7, provided with arcuate ends 18l8 where they contact the damper to which they are riveted. (See Figures 2 and 3.)

The stiifeners 17-17 at the center of the dampers 15 are securely mounted on a concentric shaft 19 that extends forwardly through a removable clean-out door 20 on the front casing 7, where it is provided with an operating handle 21.

The rear end of the shaft is journaled in a vertical bracket 22 within the flue passage 14. The damper 15 is of lesser diameter than the passage 14, and is so mounted in the door 20 and bracket 22 as to bring its surface in contact with the wall of the fiue passage at the throat 13. (See Figures 2 and 3.)

In order to prevent undue radiation of heat from the fire box through the back of the casing, I have provided a wall 23 that is attached to the rear edges of the fire box 10.

Extending longitudinally within the fire box 10, adjacent the side walls of the latter and supported by bracket clips 2424 on the front casing 7 and clips 25-25 on the back wall 23, are two grate supports 2626 for a portable, slidable, rectangular frame 2'7 for a revolving grate 28. The frame 2'7 has riveted to one side of its front portion a U-shaped bracket 29 having rotatably mounted between its open ends, a roller 30; and on the rear portion of the same side of the frame 2'7 there is another bracket 29 carrying a roller 30. (See Figures 2 and 6.) On the other side of the front portion of the frame 27 there is secured a U-shaped bracket 31 in whose bifurcated ends a shaft 32 is journaled that projects forwardly through a hole in a grate cover plate 33 bolted to the front wall '7 and terminating in a crank handle 34. The shaft also projects rearwardly through another U-shaped bracket 35 similar to the bracket 31 and in whose bifurcated ends it is also journaled.

The frame 27 and the grate 28 which it carries, are free to be removed through the opening covered by the plate 33 in the front wall 7 for cleaning and repair. The fixed supports 26 are apertured to receive rollers 26 upon which the 110 grate supporting frame 27 is slidable wholly into the fire box, and out of the same.

Fixedly mounted upon the shaft 32 carried by the slidable frame 27, between the open ends of each bracket 31 and 35, is a flanged pinion 36. The grate 28, which is rotatably mounted upon the rollers and pinions 36, constitutes a series of ring-shaped grate bars 37, each having on oppositely disposed faces, circumferentially spaced, apertured bosses 38. (See Figures 3 and 4.)

The bars 3'? are placed in axial alinement, and receive through the apertured bosses 38 tie rods 39. Upon their protruding threaded ends are mounted end rings 40-40, the entire assembly being drawn tightly together by hex-nuts 41 placed on threaded ends of the rods 39. These end rings 4c -4o, which have substantially the same inside diameter as the bars 3'7, are formed upon their peripheries with a stepped shoulder 42. Gear teeth 43 are out upon the outer face of this shoulder for engagement by the pinions 36-36, while the stepped shoulders 42 receive the rollers '3il--30 as shown in Figure '6. Now,

.. when the handle 34 is rotated, the grate will also rotate to sift out the ashes into an ash pit 44 formed by the fire box 16 below the grate 28, for which a clean out door se is hingedly secured in an opening 45 in the front 7. (See Figures 3, 4,

5 and 6.) The rear end ring 46 is partially closed by the bars 40 to prevent fuel from being forced out through the rear end of the grate.

Positioned above the grate 28 and extending longitudinally of the fire box 10, is a series of 7 steel angles 46 arranged as shown at Figure 3 and covered with fire brick 4B or similar material to retard the passage of heat and conduct it to the walls of the fire box 16. The angles 46 are supported by a ledge 47 on the inside of the front 7, and a shelf 48 attached to the wall 23. (See Figures 2 and 3.) The space between the fire box it and the casing l is sub-divided by a series of vertical baffie plates 49 extending from the casing to the fire box and terminating above the flue passage 14 in a longitudinal ba'iile 50, thus forming on each side of the fire box vertical passages, each of which has an outlet in the bonnet 3 through a leader connection 51 to its respective warm air leader, riser and register, (not shown) Below the floor line is a shallow pan 52 provided with continuations 52 of the baffles 49 and a longitudinal baffle 52* centered below the ash pit 44 to provide within the pan a compartment communicating with each oi"- the vertical pas sages between the baffles e9. Each compartment is supplied with a separate air inlet 52 positioned on each side of, and adjacent to, the bafiie 5-2. These inlets 52 are nested beyond the casing l to form a common inlet duct 52 The pan 52 and its ba'ilies cause the incoming air to encompass the ash pit where it is partially heated.

By this system of baffled partitions each column of heated air between the baffles can only find an outlet through its respective bonnet conmotion 51 and thus insures an even distribution of heated air through its proper warm air register.

Integral with the inner face of the cover plate below a hinged feed door 53, is a charging chute 54 whose inner converging end 55 extends into the forward open end of the grate. Opening into the rear of the fire box is a flue by-pass 56 that connects with a vertical flue 5'7, whose upper end joins the horizontal flue 14.

The lower end of the flue 57 is closed with a removable flue cap 58, and to the rearwardly extending end 57 of the flue 14, a smoke pipe (not shown) connects with a flue or chimney in the usual manner.

When adding fuel to the fire, the grate may be rotated or rocked to remove accumulated ashes, and the pivoted damper 60 provided in the flue 5'7, opened to provide a direct draft and eliminate smoking at the feed door. After the firing is completed the damper 60 is closed and the heat and combustion gases pass upwardly through the bafiie elements 46 and ic the throat l3 and out through the flue 14 to the smoke pipe. Because of this long flue passage the stack or flue temperature is materially reduced, with a corresponding increase in the efficiency of the furnace.

My rotary grate, together with the partitioned means for bringing the ascending air, first in contact with the ash compartment and then with the walls of the fire box, as well as my improved bafl'ie, damper and flue construction for increasing the radiation of heat generated within the fire box, are among the principal advantages of my heating apparatus.

I do not wish to be limited to the details of construction and arrangement herein shown and described, and any changes or modifications may be made within the scope of the subjoined claims.

Having described my invention, I claim:

1. In a heating apparatus, an outer casing, a fire box therein, having a throat portion, a long substantially cylindrical flue passage connected to the throat portion of said fire box and coextensive with the latter, in said casing, an axiai shaft mounted for rotation in said flue passage, a crank for turning said shaft, and a damper mounted on said shaft, and co-extensive with the depth of the fire box, to control the admission of the combustion gases from the fire box to the flue.

2. In a heating apparatus, an outer casing, a fire box contracted at its upper end to form a narrow elongated throat, a long substantially cylindrical horizontal flue passage in said casing above the throat portion of the fire box and in communication therewith, an axial shaft mounted for rotation in said flue passage, a crank for turning said shaf and a cylindrical damper secured on said shaft and having in its circular wall a slot co-extensive with the elongated throat in the fire box, for registry therewith.

3. In a heating apparatus, an outer casing,

a fire box therein including an ash compart- I.

ment, vertical air passages between the outer casing and the fire box to expose the ascending air to the heated walls of the latter, an air inlet pan below the bottom of the ash compartment, in

communication with the vertical passages, and 3 partition means in said pan to form air conveying passages which co-operate with vertical air passages between the outer casing and fire box.

GEORGE WILLIAM LUTZ. 

